Intestinal Abnormalities in Patients With SARS-CoV-2 Infection: Histopathologic Changes Reflect Mechanisms of Disease.

Approximately 20% of patients with symptomatic syndrome-associated coronavirus-2 (SARS-CoV-2) infection have gastrointestinal bleeding and/or diarrhea. Most are managed without endoscopic evaluation because the risk of practitioner infection outweighs the value of biopsy analysis unless symptoms are life-threatening. As a result, much of what is known about the gastrointestinal manifestations of coronavirus disease-2019 (COVID-19) has been gleaned from surgical and autopsy cases that suffer from extensive ischemic injury and/or poor preservation. There are no detailed reports describing any other gastrointestinal effects of SARS-CoV-2 even though >3,000,000 people have died from COVID-19 worldwide. The purpose of this study is to report the intestinal findings related to SARS-CoV-2 infection by way of a small case series including one with evidence of direct viral cytopathic effect and 2 with secondary injury attributed to viral infection. Infection can be confirmed by immunohistochemical stains directed against SARS-CoV-2 spike protein, in situ hybridization for spike protein-encoding RNA, and ultrastructural visualization of viruses within the epithelium. It induces cytoplasmic blebs and tufted epithelial cells without inflammation and may not cause symptoms. In contrast, SARS-CoV-2 infection can cause gastrointestinal symptoms after the virus is no longer detected, reflecting systemic activation of cytokine and complement cascades rather than direct viral injury. Reversible mucosal ischemia features microvascular injury with hemorrhage, small vessel thrombosis, and platelet-rich thrombi. Systemic cytokine elaboration and dysbiosis likely explain epithelial cell injury that accompanies diarrheal symptoms. These observations are consistent with clinical and in vitro data and contribute to our understanding of the protean manifestations of COVID-19.

Massive gastrointestinal bleeding in a patient with COVID-19.

Despite the emerging data about the thrombophilic effect of the novel coronavirus [1] , the relation between coagulation disorders and the COVID-19 pandemic is still not well understood. Various studies pointed to the significant role of the COVID-19 induced cytokine storm in development of the hypercoagulable state which leads to serious thromboembolic complications [2,3] . Some studies report the development of severe immune thrombocytopenia induced by the novel coronavirus [4] . Other studies found a correlation between COVID-19 disease and the development of disseminated intravascular coagulation (DIC) [5]. Patients with severe COVID-19 disease have an increased risk for development of gastrointestinal bleeding (GI) which may be related to stress [6] , critical illness or mechanical ventilation [7] . Further studies showed the ability of the novel coronavirus to infect the epithelial cells of the GI tract [8] . Moreover, some data pointed to the ability of the virus even to infect the endothelium of blood vessels [9]. The relation between the COVID-19 pandemic and GI bleeding deserves more studies [10]. We present a case of GI bleeding in a patient with severe COVID-19 disease. We assume that COVID-19 disease can be a predominant factor for the development of DIC and GI bleeding.

Cytomegalovirus haemorrhagic enterocolitis associated with severe infection with COVID-19.

We present a case of haemorrhagic enterocolitis in a patient with SARS-CoV-2 who recovered from respiratory failure after support with venovenous extracorporeal membrane oxygenation. We describe clinicopathological features consistent with the systemic coinfection/reactivation of cytomegalovirus (CMV) concurrent with COVID-19 infection and the protracted clinical course of resolution of gastrointestinal inflammation after the treatment of CMV infection. Stool PCR, abdominal CT perfusion scan and histological examination of ileal and colonic tissues excluded enterocolitis secondary to other causes of infection (common viral, bacterial and protozoal gastrointestinal pathogens), macrovascularand microvascular ischaemia and classic inflammatory bowel disease, respectively. We propose possible synergistic pathophysiologic mechanisms for enterocolitis complicating severe COVID-19 infection: (1) T lymphocyte depletion and immune response dysregulation, (2) use of immunomodulators in the management of severe COVID-19 infection and (3) high concentration of ACE-2 receptors for COVID-19 virus in the gastrointestinal tract.

A severe coronavirus disease 2019 patient with high-risk predisposing factors died from massive gastrointestinal bleeding: a case report.

BACKGROUND: SARS-CoV-2 is highly infectious and has been a significant public health threat. Despite typical manifestations of illness are dominated by respiratory symptom, some patients have concurrent gastrointestinal manifestations, including nausea, diarrhea, and vomiting. Massive gastrointestinal bleeding, however, has rarely been reported. CASE PRESENTATION: We herein described a case of severe SARS-CoV-2 infected patient with several risk factors for poor prognosis, including male, hypertension, old age, mixed bacterial infection and multilobular infiltration on radiological imaging. After improvement of respiratory status, the onset of gastrointestinal bleeding occurred, probably resulting from direct viral invasion as evidenced by the positive findings for SARS-CoV-2 in the repeat stool specimens. Although aggressive resuscitation was administered, hematochezia was uncontrolled. The patient rapidly deteriorated, suffered from cardiac arrest, and expired. CONCLUSIONS: Digestive symptoms could be severe in SARS-CoV-2 infected patients, especially for the high-risk individuals with predisposing conditions. A more thorough protocol for preventing cross-infection through faecal-oral transmission should be implemented in the process of patient care and infection control.